[LoopPeel] Handle non-local instructions/arguments when updating exiting values (#142993)

Similar to
https://github.com/llvm/llvm-project/commit/7e14161f49b32387988cf9d937bbfaa27d0fbdd5,
the exiting value may be a non-local instruction or an argument.

Closes https://github.com/llvm/llvm-project/issues/142895.

1 files changed, 5 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Utils/LoopPeel.cpp b/llvm/lib/Transforms/Utils/LoopPeel.cpp
index bd025fd..9149f71 100644
--- a/llvm/lib/Transforms/Utils/LoopPeel.cpp
+++ b/llvm/lib/Transforms/Utils/LoopPeel.cpp
@@ -1257,7 +1257,11 @@ bool llvm::peelLoop(Loop *L, unsigned PeelCount, bool PeelLast, LoopInfo *LI,
     // Now adjust users of the original exit values by replacing them with the
     // exit value from the peeled iteration and remove them.
     for (const auto &[P, E] : ExitValues) {
-      P->replaceAllUsesWith(isa<Constant>(E) ? E : &*VMap.lookup(E));
+      Instruction *ExitInst = dyn_cast<Instruction>(E);
+      if (ExitInst && L->contains(ExitInst))
+        P->replaceAllUsesWith(&*VMap[ExitInst]);
+      else
+        P->replaceAllUsesWith(E);
       P->eraseFromParent();
     }
     formLCSSA(*L, DT, LI, SE);